Diagnostic device



FIG. 1 is a perspective view of a diagnostic device in accordance with my new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a front view thereof;

FIG. 4 is a right side view, the left side view is mirror image thereof; and,

FIG. 5 is a rear view thereof.

The broken lines are included for the purpose of illustrating portions of the diagnostic device that forms no part of the claimed design. 

The ornamental design for diagnostic device, as shown and described. 